Autopolisher



May 7, 1940. J. D. THOMPSON AUTOPOLISHER 'Filed Oct. 13, 1939 2Sheets-Sheet 1 Q QK J. Th0mpa07z I N VEN TOR.

ATTORNEYS.

May 7, 1940. J. D. THOMPSON AUTOPOLISHE R Filed Oct. 13, 1939 2Sheets-Sheet 2 mm, f

VII/1A.:

ATTORNEYS.

Patented May 7, 1940 a NITE STATES PATENT OFFICE JamesDorsey Thompson,West Medford, Mass. Application October 13, 1939, Serial No. 299,373

Claims.

This invention relates to a sanding and polishingmachine, theprimary-object of the invention being toprovide amachine of this. character having a movable plate or shoe over-which the sanding orpolishingycloth is stretched, the machine beingof the portabletype sothat it may be conveniently held inthe hand of the operator and readilymoved over the surface un der treatment.

An important object of the invention is to provide a portable pneumaticmachine for sanding and polishing surfaces, wherein the shoe or plate.supporting the-sanding or polishing cloth, is rapidly reciprocated toaccomplish the sanding or polishing result.

With the foregoing and other objects in View, which will appear as thedescription proceeds, the invention resides in-the combination andarrangement of parts and in the details of construction hereinafterdescribed and claimed, it

being understood that changes inthe precise embodiment of the inventionherein described, may

be made within the scope of what is claimed, without departing from thespirit of the invention:

Referring to the drawings:

Figure 1 is a plan View of a sanding and polishing machine constructedin accordance with the invention, a portion of the cover thereof havingbeen removed illustrating-the inner structure.

Figure 2 is a sectional view taken on line 22 of Figure 1;

Figure 3 isa vertical sectional view taken on line 3-3 of .Figure 2.

Figure 4 is a sectional view 'taken; on line i4 of Figure 2; I

Figure 5 isz-a sectional view taken ongline 5-5 of Figure 3. I

Figure 6'is a sectional viewtaken on line 6--6 of- Figure 2.

Referring to the drawings in detail, the body portion ofthe device isindicated generally by the reference character 5, and as shownby Figure.3 ofthe drawings. comprises a main central portion 6 bored to provideacylinder I, the base of the body portion beingwide and extendedthroughout the entire length-thereof, providing supporting surface 8, sothat one end thereof will extend beyond the supporting surface, pro-Vidinga substantially long and wide sanding or buffing surface.

The edges of the shoe or plate 9 extend upwardly as at it and overliethe longitudinal edges of the supporting surface 8, so that the shoe oring the sanding or polishing clothto the shoe or plate. Blocks indicatedat I 6 bear against the upwardly extended ends I5 of the shoe orplate 9,and are provided with threaded openings toreceive thethreaded ends ofthe piston rod II. v

The sanding or polishing cloth in the present showing, is indicated bythe reference character I! and is shown. as having one of its endsextended over the upwardly extended end of the shoe or plate 9 andclamped between the block I6 and upstanding end of the shoe or plate,securing the sanding or polishing cloth in position at this end ofthemachine. The opposite end of the sanding or polishingcloth I1 is woundon the roller I8 and passes downward-1y through the Wax container I9,from-where it is stretched over the outer surface of the shoe or plate9. Thus it will be seenthat due to this construction, wax may be readilyapplied to the surface under treatment. I

The wax container I 9 is removably held in position bymeans of thespring arms 29 so that it maybe readily and easily disconnected from themachine, when the machine is to be used in sandpapering, and a' strip ofsanding cloth is stretched over the shoe or plate 9. When a strip ofsanding'clothis used, both ends'of the sanding cloth are clamped betweenthe blocks I6 and upturned ends'of the shoe or plate 9.

V The bodyportion Sis provided with lateral passageways 2| and 22 whichcommunicate with the cylinder 7, at the ends thereof, the inner end ofthe passageway 2| being extended ups wardly, the passageway terminatingat thezupper edge of the body portion.

The passageway 22 also extends towards the center of the body portionand has its inner end disposed upwardly terminating at the upper edge ofthe body portion.

Disposed between the upwardly extended ends of the passageways 2i and22, is a passageway 23 providing the exhaust passage of the machine.

The handle of the machine is indicated by the reference character 24 andis in the form of a casting adapted to be bolted onto the upper surfaceof the body portion, as shown by Figure 1 of the drawings. The handlesection 24 is pro vided with a central hollowed-out portion providing ahousing for the movable valve member 25 which is shown as mountedtherein, the valve member 25 being secured to the vertical shaft 26, towhich the arm 21 is secured. This arm 2'! is of a length to extenddownwardly over the side of the body portion, the right angled end 28thereof being disposed directly over the control rod 29 mounted insuitable bearings formed in the body portion, and having connection withthe ends of the shoe or plate 9. Adjustably mounted on the control rod29, are nuts 30 that are adapted to engage the lug 3! extendingdownwardly from the right angled end 28 of the arm 21, so that as thecontrol rod 29 reciprocates, the arm 2'! will be operated accordingly,moving the valve 25, for purposes to be hereinafter more fullydescribed.

The valve 25 is formed with a curved bore 32 which is adapted toregister with one end of either the bore 2! or 22, and the exhaustpassageway 23. It will be obvious that when the valve member is moved toone of its positions to exhaust air from one side of the piston, the'airwill be entering the opposite bore to move the piston in the oppositedirection.

The bore 33 formed in the handle section of the machine, constitutes theintake bore or passageway through which the compressed air enters themachine, from the hose 34 which may be connected with any suitablecompressed air supply. Mounted in the handle of the machine at a pointadjacent to the intake end of the bore 33, is a valve 35 the stem 36 ofwhich extends inwardly directly under the grip 31 of the handle. Thisvalve is of a construction to open under the pressure of the airentering through the hose 34. A lever indicated at 38 has pivotalconnection with the handle and has one of its ends disposed adjacent tothe free end of the rod 36 so that as the lever-is moved inwardly to theposition shown in full lines in Figure 6 of the drawings, the valve willbe moved to its closed position, or to a position to cut off the flow ofcompressed air into the cylinder. When the lever is released by theoperator, the valve will be moved to its open'position, and thecompressed air may flow into the cylinder' to operate the piston l2.

Thus it will be seen that due to this construction, the action of thepiston l2 to accomplish the operation of the shoe Or plate 9, may be controlled at the will of the operator.

- What is claimed is:

1. A device of the class described, comprising a body portion, ahorizontal cylinder formed in the body portion, and having a widesupporting surface, a shoe slidably mounted on said supporting surface,a piston rod operating throughthe cylinder, a piston mountedintermediate the ends of said rod and disposed within the cylinder,clamping means at the end of the rod for clamping a surface treatingcloth thereto, and means for directing air to the cylinder alternatelyat opposite sides of the piston for reciprocating the piston and shoe.

2. A device of the class described comprising a body portion, ahorizontal cylinder formed in the body portion and having a widesupporting surface, a shoe slidably mounted on said supporting surface,a piston rod operating through the cylininder, a piston disposedintermediate the ends of the rod and operating within the cylinder,means for directing air alternately to. opposite sides of the piston forreciprocating the piston and piston rod, a reciprocating shoe mounted onthe supporting surface, a clamp at each end of said shoe for clamping asurface treating cloth to the shoe, and a valve for controlling thepassage of air under pressure to the cylinder.

3. A device of the class described comprisin a body portion, ahorizontal cylinder formed in the body portion and having a widesupporting surface, lateral passageways extended along the sides of thecylinder and having their outer ends communicating with-the cylinder,the opposite ends of the passageways being open, said body portionhaving an exhaust opening, a movable valve member having an openingadapted to establish communication between one end of one of thepassageways and the exhaust opening at each movement of the valvemember, "a valve housing in which the valve member is mounted, saidvalve housing having an opening through which air enters, said valveadapted to operate to control the passage of air to opposite sides ofthe piston alternately for reciprocating the piston, a reciprocatingshoe mounted on the wide supporting surface, and a surface treatingcloth mounted on the shoe and movable with said shoe.

4. A device of the class described comprising a body portion, ahorizontal cylinder formed in the body portion, said body portion havinga wide supporting surface, a shoe slidably mounted on the supportingsurface, a piston mounted intermediate the ends of said rod andoperating in the cylinder, blocks secured to the ends of the piston rod,the shoe havingupturned resilient ends, blocks secured to the ends ofthe piston rod and adapted to clamp a surface treating cloth againstsaid upturned ends of the shoea valve for controlling the passage of airto said cylinder, and means for operating said valve to control thepassage of air to oppositesides of the piston alternately, and amanually controlled valve for controlling the passage of air to'thefirstmentioned valve.

5. A device of the class described comprising a body portion, ahorizontal cylinder formed in the body portion and having a widesupporting sur face, a shoe slidably mounted over said support

